Asp.Net Core NLog日志的使用

1. 新建Asp.Net Core MVC项目

2. 从Nuget上一次安装 NLog、NLog.Config、Nlog.Extensions.Logging

3. Startup.cs——>Configure方法增加 ILoggerFactory的入参并添加NLog

   public void Configure(IApplicationBuilder app, IHostingEnvironment env,ILoggerFactory loggerFactory)
   {
   loggerFactory.AddNLog();`

4. 在HomeController中添加代码：

private readonly ILogger _logger;

    public HomeController(ILogger<HomeController> logger)
    {
        _logger = logger;
    }
    
    public IActionResult Index()
    {
        _logger.LogInformation("您访问了首页");
        _logger.LogWarning("您访问了首页");
        _logger.LogError("您访问了首页");
        return View();
    }

6. 编辑NLog.Comfig文件
   根据实际需要编辑与

<?xml version="1.0" encoding="utf-8" ?>
<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      autoReload="true"
      throwExceptions="false"
      internalLogLevel="Warn" internalLogFile="nlog-internal.txt">

  <!-- optional, add some variables
  https://github.com/nlog/NLog/wiki/Configuration-file#variables
  -->
  <variable name="myvar" value="myvalue"/>

  <!--
  See https://github.com/nlog/nlog/wiki/Configuration-file
  for information on customizing logging rules and outputs.
   -->
  <targets>

    <!--
    add your targets here
    See https://github.com/nlog/NLog/wiki/Targets for possible targets.
    See https://github.com/nlog/NLog/wiki/Layout-Renderers for the possible layout renderers.
    -->

    <!--
    Write events to a file with the date in the filename.
    <target xsi:type="File" name="f" fileName="${basedir}/logs/${shortdate}.log"
            layout="${longdate} ${uppercase:${level}} ${message}" />
    -->
    <target xsi:type="File" name="allfile" fileName="nlog-all-${shortdate}.log" layout="${longdate}|${logger}|${uppercase:${level}}|${message}${exception}"></target>
    <target xsi:type="File" name="ownFile-web" fileName="nlog-own-${shortdate}.log" layout="${longdate}|${logger}|${uppercase:${level}}|${message}${exception}"></target>
    <target xsi:type="Null" name="blackhole"></target>
  </targets>

  <rules>
    <!-- add your logging rules here -->

    <!--
    Write all events with minimal level of Debug (So Debug, Info, Warn, Error and Fatal, but not Trace)  to "f"
    <logger name="*" minlevel="Debug" writeTo="f" />
    -->
    <logger name="*" minlevel="Trace" writeTo="allfile"></logger>
    <logger name="Microsoft.*" minlevel="Trace" writeTo="blackhole" final="true"></logger>
    <logger name="*" minlevel="Trace" writeTo="ownFile-web"></logger>
  </rules>
</nlog>